The present invention relates to an air ventilation or air supply system which is used for air supply or air ventilation in mainly houses, atria and gymnasiums.
As systems using induction effect, there have been proposed an arrangement wherein the induction effect of fresh air is utilized to exhaust contaminated air, and another arrangement wherein fresh air is compressed to form a high velocity jet, a venturi and an orifice are combined to promote the induction effect so as to increase ventilation airflow rate, and the Coanda effect is utilized. As an example of the former prior art, there have been an arrangement which has been disclosed in e.g. JP-A-60-218545, and which is constituted so that the induction effect of fresh air is utilized to exhaust contaminated air. In FIG. 59, there is shown a schematic view of such a type of air ventilation or air supply system.
In this figure, reference numeral 1 designates a wall for partitioning an indoor side 2 and an outdoor side 3. Reference numeral 4 designates a range which is arranged in the indoor side 2, and produces contaminated air. Reference numeral 6 designates a range hood which is arranged above the range 4. Reference numeral 7 designates an exhaust duct which passes through the wall 1, and which has one end connected to the hood 6. Reference numeral 8 designates a blower which is arranged in the outdoor side 3. Reference numeral 9 designates an air supply duct which has one end connected to the blower 8, and has an intermediate portion connected to the exhaust duct 7. Reference numeral 10 designates outdoor air.
In operation, when the blower 8 is driven, the outdoor air 8 in the outside 3 is supplied into the air supply duct 10. By the air blowing through the air supply duct 9, the contaminated air 5 from the range 4 is inspired into the air supply duct 9 through the hood 6 and the exhaust duct 7 and exhausted therefrom.
In such an arrangement, only a small part of the air supply capability (air supply volume) of the blower 8 is utilized for exhaustion of the contaminated air 5 from the indoor side 2 to the outdoor side 3. A large part of the air supply capability is utilized to inspire the fresh air 10 in the outdoor side 3 and lead it into the outdoor side 3 through the air supply duct 9.
In FIG. 60, there is shown a schematic view of a conventional air ventilation or air supply system using compressed air, which has been disclosed in e.g. JP-A-6-280800.
In this figure, reference numeral 11 designates a connecting pipe which has one end connected to a blower 8. Reference numeral 12 designates a pressure chamber which is connected to the other end of the connecting pipe. Reference numeral 13 designates a venturi which passes through the pressure chamber 12, and which has a conical portion 14 and a cylindrical portion 15 smoothly coupled together to provide a flare shape. Reference numeral 16 designates an orifice which provides an annular space 17 between the conical portion 14 and itself, and which has a central portion formed in a hollow shape and communicated with an indoor side 2 and the inside of the venturi 13.
In operation, when a primary air 18 pressured by the blower 8 is led into the pressure chamber 12, the velocity of the primary air 18 is increased while the flow of the primary air (primary flow) is passing through the annular space 17, and the primary air is blown out into the venturi 13 toward an outlet 19. As a result, the induction effect is generated in the venturi 13 and in the orifice 16 to inspire indoor air 20 from an inlet 21, causing the indoor air to be exhausted from the outlet 19 into an outdoor side 3 after the indoor air has passed through the orifice 16 and the venturi 13.
In such an arrangement, only a small part of the pressurization capability of the blower 8 is utilized for exhaustion of the indoor air 20 into the outdoor side 3. A large part of the pressurization capability is utilized to lead out the fresh air into the outside 3 from the pressure chamber 12 through the annular space 17 and the outlet 19.
Since the conventional air ventilation or air supply systems using the induction effect have been constructed as stated earlier, the former prior art has created a problem in that exhaust performance can not be obtained in a sufficient manner because exhaust volume is limited to the induced airflow rate. On the other hand, the latter prior art has created a problem in that the high velocity jet is too noisy to reduce noise in addition to the problem involved in the former prior art.